A Study to Evaluate the Safety and Efficacy of THR-317 for the Treatment of Diabetic Macular Oedema (DME)

Inclusion criteria: * Male or female aged 18 years or older * Type 1 or type 2 diabetes * Centre-involved DME with CST ≥ 340µm on Spectralis SD-OCT or ≥ 320µm on non-Spectralis SD OCT, in the study eye * Reduced vision primarily due to DME, with BCVA between 72 and 23 ETDRS letters read at 4 meters (20/40 and 20/320 Snellen equivalent) in the study eye * Anti-vascular endothelial growth factor (anti-VEGF) treatment naïve study eye or poor response to prior anti-VEGF treatment in the study eye * Non-proliferative diabetic retinopathy, or stable proliferative diabetic retinopathy without neovacularisation at the disc * Written informed consent obtained from the subject prior to screening procedures Exclusion criteria: * Concurrent disease in the study eye, other than DME, that could compromise BCVA, require medical or surgical intervention during the study period or could confound interpretation of the results * Previous treatments / procedures in the study eyes as follows, or their planned use during the THR-317 treatment period for up to 30 days after the last injection: panretinal or focal / grid laser photocoagulation \[3 months\], anti-VEGF treatment \[any time for anti-VEGF naïve subjects; 4 weeks for subjects with a poor response to anti-VEGF treatment\], intra-ocular or peri-ocular corticosteroids \[4 months\], steroid implant \[any time\], intra-ocular surgery \[3 months\], vitrectomy \[any time\] * Any active ocular / intra-ocular infection or inflammation in either eye * Aphakic study eye * Untreated diabetes * Glycated haemoglobin A (HbA1c) \> 12% * Uncontrolled hypertension in the opinion of the Investigator * Pregnant or lactating female or female of child-bearing potential not utilising an adequate form of contraception or male of reproductive potential not utilising contraception suggesting lens / zonular instability